Cable insulation cutter



E. F. cHlsENA 2,647,309

Aug. 4, 1953 v CABLE INSULATION CUTTER Filed May 22, 1950 16\ J6 z2 17\/ I g@ 6 @759 3. s i 6 a 32 6/%/ \19 Z 1x5 /NVEA/TOA.

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2 A f/M Z Patented Aug. 4, 1953 fi vUNITED sTATEs PATENT OFFICE CABLE INSULATIONv CUTTER Ernest F. Chisena, Brooklyn, N. Y.

Application May 22, 1950, Serial No. 163,467

3 Claims.`

My invention is an improved cable insulation cutter, and more particularly an implement for slitting the outer tubular casings of electric cables when part of the casing or sheath has to be opened to give access to the insulated conductors inside the cable.

An important object of this invention is to provide ahandy implement which can leasily be manipulated by an electrical lineman tocut the outside sheath'of an electric cable without risk of injury to ones hands or fingers. Such cables have tubular casings or sheaths of metal such as lead, or other protective material which is resistant to the edge of a cutting blade and if the workman had to rely upon an ordinary knife, the operation would be risky and difcult. With this invention the slitting of such a sheath or casing is greatly facilitated, and all danger of injury is obviated. The implement not only opens the casing quickly but also holds the cable securely while the operation is being performed,

In its preferred form, the implement comprises a frame' or body in which are mounted suitable members for seating the cable, and a cutting member for severing the sheath or casing in the manner required. Both the seating members and the cutting member are movable, and the implement has means for operating the seating members and shifting the frame, so that the cutting is progressively and smoothly accomplished from start to finish. y

The drawings illustrate a preferred embodiment of the invention, and the construction and mode of use are fully explained herein. But the disclosure is by way of example only and I may vary the structural details without departing from the general combination of parts dened in the appended claims.

On the drawing:

Figure 1 is a top plan of a cutting implement according to this invention.

Figure 2 is a side view thereof,'partly broken away and in section.

Figure is a section on line 3-3 of Figure 2.

Figure 4 is a view showing a detail in modified form, and v Figures 5 and 6 are respectively a side and sectional view of another design of parts associated with the cutter member of the implement.

The body or framework I has a continuous side 2, between the two ends, but the opposite side 3 has a gap 4 The framework thus has approximately the shape of a C when viewed edgewise, and the gap 4 gives admission to the lil cable 5. This'framework can be made of plastic, metal, wood, or other'suitable material. At one side of the gap or opening 4 the framework carries a rotatable cutting disk 6 having an acute edge around the rim; and at the opposite side of the gap is a shaft 'I, parallel to the axis of the cutter member, with one end 8 square for engagement by a tool, and projecting to the outside of the body I. The sides 2 and 3 have openings with bearing sleeves or linings 9 in which rounded portions I 0 of the shaft are seated. Between the portions I0 the shaft is preferably square as indicated at I I, and on this square section are two bevelled gears I2. These gearsv face each other and the teeth thereof have edges which effectively engage the cable 5. The gears are separated by a washer I3 and a similar washer is between each gear and the adjacent sleeve A9.

The cutter member 6 is rotatably mounted in a slidable crosshead I4 disposed between the side 2 and part of the side 3. This crosshead is shaped like the letter U lying on one side and has arms I5 in contact with the inner faces of the sides 2 and 3. To the crosshead are secured side plates I6 by screws I'I, these plates overlapping the sides 2 and 3 to maintain the head in position. The ends of the arms I 5 of the yoke-shaped head carry a pin I 8 on which the disk 6 turns, and this disk is flanked by bevel gears I9 on the pin I 8 to serve as reentrant guiding means for the disk 6. The shaft 'I and pin I8 are parallel, and the cable 5 is firmly held between the gears I2 and I 9 during the cutting operation. The pin I8 is held in place by a small locking screw 20.

In the part or base of the yoke-shaped member I4 is a threaded opening 2l which receives a threaded stud 22, extending out througha bearing open-ing in the end of the frame I and having a knob 23 on its outer end, which has a squared portion 2I. A locking screw 25 aixes the knob 23 to the end 24 so that the stud can be turned. On the stud is a collar 26 abutting the inner face of the adjacent end of the body I and acting in conjunction with the knobto prevent longitudinal movement of the stud 22. Hence, by rotation of knob 23 the disk 6 is forced against the cable or retracted. Between the collar 26 andthe knob23 the stud is round as indicated 4at 2l'.

In use the implement is manipulated to get the cable into the gap 4, laying the cable against the gears I2. The knob is then turned to force the sharp rim of the cutter disk 6 into the outer sheath of the cable and bring the gears I9 into engagement with it. In this position of the parts the edge of the disk 6 is deep enough in the cable to cut through the sheath; and then a tool 28 is slipped upon the end 8 of the shaft I and the gears i2 turned. Thus the implement is fed along the length of the cable as far as the cutting or slitting should be accomplished. The cable is firmly held in the body l and there is no risk of injury to the workman.

If desired the sides 2 and 3 can have additional openings.:29 to locate the shaft 1 farther from the disk B when large cables are to be cut.

The implement is simple and inexpensive, easy and certain in operation, and is well adapted to serve its intended purpose.

In Figure 4 a different type of gear 30 to be mounted on the shaft 1 is illustrated.y This gear 30 is also bevelled or conical and. has several annular rows of teeth 3i of different diameters. With two such gears the implement works better with large or small cables, particularly the latter.v :figures 5.and -illustrate a head fcarrying the cutterdisk 6 kwith guidernembersti associated .with the disk t instead. of gearsla This head is-z merely ablock with a-.slot for ,the Vdisk 8 and-retainer. or guide plates I3. as before affixed tofitssides.A The head'32 is` again adjusted by means of a knob. 23vand a threaded stud 22 ,engaging afthreaded; opening 2i inthe rear ofthe head. The guide ribs-33 project beyondthe front offthe head. and their. forward edges are spanned by aiplate 311v having a slot. 35 through which the disk S-projects. -The guide members or .ribs 33 extend across the plate 34 above and below the slot-'35. and have. concave; faces 36., inclined in- Ward like-'the rims of the .disks-5 towards `the s101235. Theplate-,Sd is made. fast totherhead 33by, screws or` other fasteners 31. ,This crosshead can advantageously be `used l.with-.the type of .gears 3i)` shown onFigure 4. Having vdescribed my invention, Vwhat I- believe tobe new is:

. l.` An implement for longitudinally slitting the outer-tubularcasingsof cables comprising a C- shaped frame having a gap in one side, a shaft rotatably supported in said frame adjacentsaid gap,:bevelled gears facing each other mounted on` said shaft to turn therewith, said shaft having an end projecting fromthe frame and shaped for engagement by a tool, a cross head slidably mounted inthe frame, the gap beingbetween theshaft and the head, guide plates on the sides of the head overlapping-and: engaging thewouter sides of. the-frame, a pnon said head parallel toY said shaft, arotatable cutterdisk: on the. pin

projecting from the frontend ofthe head.; guide means having faces inclined towards the disk-on the-front of the head and projecting therefrom adjacent both faces of the disk inline with said gears, the gap permitting passage of a cable be-` tween the disk and said gears, to be-engaged on opposite sides by the gears and guide means, a threaded stud in the frame and engaged so as to be held against longitudinal movement, a knob on the stud to turn the stud, the head having a threaded bore receiving said stud.

2. An implement for longitudinally slitting the outer tubular casings of cables lcomprising a C- shaped frame, having a gap in one side, a shaft rotatably supported in said frame, adjacent said gap, bevelled gears facing each other mounted on said shaft to turn therewith, said shaft having an end projecting from the frame and shaped for engagement by a tool, a cross head slidably mounted in the frame, the gap being between the shaft and the head, guide plates on the sides of the head overlapping and engaging the outer sides of the frame, a pin on said head parallel to said shaft, a rotatable cutter disk on the pin projecting from the front end of the head, guide means having faces inclined towards the disk on -vthe front of the head and projecting therefrom `adjacent both faces of the disk, in line with said gears, the gap permitting passage of a cable between the disk and said gears to be engaged on opposite sides .by the gears and guide means, a

threaded stud in the frame and engaged so as iin-beheld against longitudinal movement, a knob on the stud to turn the stud, the head having a--threadedbore receiving saidstud, said .head being yoke-shaped with its arms presented .to said. gears, said guide. meanshaving the form of r additionali bevel gears rotatablyV mounted. on said pin, withtheir sncallery ends abutting said disk.

3. An implement for longitudinally slitting the outer tubular casillas of cables comprising a C- shapedframe, having a gap in one side, a ,shaft rotatably .supported in said .frame adjacent said gap, bevelled gearsfacing eachothermounted onsaid shaft to .turn therewith,.said shafthaving an end projectingfrom the frame and shaped for Yengagement by a tool, a cross headslidably mounted inthe frame the. gap beingv `between the shaft andthe head, guide plates Aon the sides of thehead overlapping and engaging the y.outer sidesof the frame, apinon said headparallel tcsaid shaft, a rotatable .outer disk .on the pin projecting from the front end of the'head, guide means.. havingfaces inclined y, towards the disk on the front of the head and projecting V.therefrom adjacent both faces ofthe disk in line with saidgears, the gap permitting passage. of a cable between. the disk andlsaidgears, to. be engaged en oppositesides bythe gears andguide means, athreaded stud in the frame. and .engaged so as to. be held .against longitudinal movement, a knob on the stud toturn the stud, ,they head `having a threaded bore receiving. said stud,said head having a slot in its front receiving said disk with the edge of the .diskprojecting fromthe slot, aclosure plate .spanning the front ends of said guide means and having a slot forsaid disk. said guide means having the. form of ribs onsaid closure-plates along both edges. of said slot.

Ertsris'r F. CHISENA.y

References cites in the fue of this patent -..UNITED STATES PATENTS Number Name Date 927,345 f Furlong July 6, 1909 1,798,683 Korab Mar. 31,1931 1,801,311 Johnson Apr. 21,1931 1,835,597 Hill et'al. Dec; 8,` 1931 2,346,227 Martin et al Apr. 11, 1944 2,374,753 Kramer May l, 1945 2,391,722 Lundeen Dec. 25, 1945 

